Embodiments of the present invention relate to a backlight module of a liquid crystal display.
At present, LCDs (liquid crystal displays) have become the majority types of flat panel displays. As liquid crystal in a LCD per se does not emit light, a LCD needs a backlight module as a light source to display images. Most of the LCDs of related art are of transmitting type, and a backlight module is a necessary component part of a transmitting type LCD.
In the backlight modules of the related art, LEDs (light-emitting diodes) can be used as light sources. FIG. 1a is a schematic view of a backlight module of the related art using white LEDs. FIG. 1b is a schematic sectional view taken along line A-A′ of FIG. 1a. As shown in FIGS. 1a and 1b, the backlight module of the related art comprises a substrate 20 for disposing LEDs thereon and white LEDs 10. Substrate 20 has a structure of honeycombed protrusions, and a white LED is provided on each of the honeycombed protrusions.
For improving color reproduction, a white LED can be replaced with tricolor LED, that is, a red LED, a blue LED and a green LED.
FIG. 2a is a schematic view of a backlight module of the related art using tricolor LEDs. FIG. 2b is a schematic sectional view taken along line B-B′ of FIG. 2a. As shown in FIGS. 2a and 2b, the backlight module of the related art comprises a substrate 20 for disposing tricolor LEDs thereon and red LEDs 11, blue LEDs 12 and green LEDs 13 provided on honeycombed protrusions of the substrate 20.
For a backlight module using tricolor LEDs, there is no overlapping region of light of different colors within a height range of H, and there are overlapping regions of light of only two colors within a height range of 2H. As a result, for a backlight module using tricolor LEDs, white light can be only formed outside the height range of 2H. That is, a backlight module using tricolor LEDs has a thickness increased by 2H as compared with the thickness of a backlight module using white LEDs.